Snowshoe

ABSTRACT

A plastic snowshoe having a longitudinal blade with an upturned blunt leading edge. The blade is arched from side-to-side with the concave side down to provide a ground-bearing surface. A downwardly extending &#39;&#39;&#39;&#39;skeg&#39;&#39;&#39;&#39; is positioned within the concavity of the blade to inhibit rearward slippage of the blade while still allowing forward gliding movement. A longitudinal ridge or keel extends along the center underside of the snowshoe blade to improve the structural rigidity of the blade while at the same time preventing &#39;&#39;&#39;&#39;ankle roll&#39;&#39;&#39;&#39;. A conventional binding or foot stirrup is mounted on a horizontal portion of the upper surface of the snowshoe blade. In the preferred embodiment, a removable, friction-fitted transversely extending &#39;&#39;&#39;&#39;centerboard&#39;&#39;&#39;&#39; is provided to inhibit rearward slippage on extremely steep slopes.

United States Patent [191 Dearborn 51 Sept. 4, 1973 SNOWSHOE {22] Filed:May 25, 1972 [21] Appl. No.: 256,644

[76] Inventor:

Primary Examiner-Patrick D. Lawson Att0meyC. Yardley Chittick et al.

[57] ABSTRACT A plastic snowshoe having a longitudinal blade with anupturned blunt leading edge. The blade is arched from side-to-side withthe concave side down to provide a ground-bearing surface. A downwardlyextending skeg is positioned within the concavity of the blade toinhibit rearward slippage of the blade while still allowing forwardgliding movement. A longitudinal ridge or keel extends along the centerunderside of the snowshoe blade to improve the structural rigidity ofthe blade while at the same time preventing ankle roll. A conventionalbinding or foot stirrup is mounted on a horizontal portion of the uppersurface of the snowshoe blade. ln the preferred embodiment, a removable,friction-fitted transversely extending centerboard is provided toinhibit rearward slippage on extremely steep slopes.

10 Claims, 3 Drawing Figures SNOWSHOE BACKGROUND OF THE INVENTION Thepresent invention relates to snowshoes in general and, moreparticularly, to an improved snowshoe having a downwardly opening,arched, longitudinal, blade with means for inhibiting rearward slippageof the blade while still allowing forward gliding movement of thesnowshoe.

Conventinnal, racket-shaped snowshoes provide adequate flotation andtraction for the wearer in deep unpacked snow. However, the existingsnowshoes offer no possibility for gliding and so must be picked up andout of each footprint and placed just ahead in a deliberate and measuredgait. With these constraints, the wearer is limited in his pace throughuntracked deep snow. By increasing his pace, the wearer invites disasterin the form of catching the leading edge of the snowshoe in the snow.

It is, accordingly, a general object of the present invention to providean improved snowshoe design.

It is a specific object of the present invention to provide a snowshoeutilizing a pair of lightweight ski-like runners.

It is still another object of the present invention to provide animproved snowshoe which can be readily and inexpensively fabricated fromconventional plastic materials.

It is a feature of the present invention that the improved snowshoedesign provides the conventional functions of a standard snowshoe interms of floatation and traction, but which also provides a wearer withadditional advantages of forward gliding.

It is still another feature of the present invention that the improvedsnowshoe includes means for inhibiting rearward slippage of the snowshoewhile still allowing forward gliding movement.

It is a further feature of the present invention that the convex uppersurface portion of the snowshoe allows the wearer to easily lift thesnowshoe out of deep, unpacked snow.

These objects and other objects and features of the present inventionwill best be understood from a detailed description of a preferredembodiment thereof, selected for purposes of illustration and shown inthe accompanying drawings, in which: 21

FIG. 1 is a view in perspective of the improved snowshoe of the presentinvention showing a portion thereof broken away;

FIG. 2 is a front elevation of the improved snowshoe; and,

FIG. 3 is a view in perspective showing the underside of the improvedsnowshoe.

Turning now to the drawings, there is shown an improved snowshoeconstructed in accordance with the present invention and indicatedgenerally by the reference numeral 10. The snowshoe comprises alongitudinal blade 12 having an upwardly extending leading edge 14, ahorizontal portion 16 which provides a mounting surface for a bootbinding 18 (shown in FIG. 3) and, in transverse cross-section, adownwardly concave snow-engaging lower surface portion 20 and anupwardly convex upper surface portion 22. Suitable boot mounting holes24 are provided in the horizontal boot mounting surface 16 toaccommodate threaded fasteners (not shown) for securing the boot binding18 to the blade. It will be appreciated that various mounting systemscan be used to secure the conventional boot binding to the blade 12. 6

Although the improved snowshoe 10 can be fabricated from a variety ofmaterials utilizing known fabrication techniques, it has been found thata fiberglass reinforced high density polyethylene is quite desirable.Thus, in the preferred embodiment, the longitudinal blade 12 is formedby injection molding a glass fiber reinforced high density polyethylene.The polyethylene provides the desired surface lubricity for the lowersnow-engaging portion 20 and the upper convex surface portion 22.

Given the smooth configuration of the snowshoe 10, it will beappreciated that in deep unpacked snow the wearer can glide forwardlyduring each step. This is in contrast to existing snowshoes which offerno possibility for gliding. With existing snowshoes, each shoe must bepicked up out of each footprint and placed just ahead in a deliberateand measured gait. With such snowshoes, increasing the pace invitesdisaster in the form of a leading edge caught in the snow. With the im'proved snowshoe 10, the wearers gait more closely resembles that ofnormal walking. Thus, each foot can be advanced as it is beingunweighted, not after it is un weighted. This combined with the glidingability of the snowshow 10 makes for a pace which is substantiallyfaster than that of conventional snowshoes with a concomitant reductionin physical effort.

ln order to prevent rearward slipping movement of the snowshoe bladeinhibiting while at the same time permitting the desired forward glidingmovement of the blade, suitable anti-backslip means indicated generallyby the reference numeral 26 are provided rearward the showshoe It]. Theanti-backslip means 26 can be formed in a variety of ways. For example,a downwardly extending transverse skeg 28 can be integrally moldedwithin the lower concave snow-engaging portion 20 of the blade. The skeg28, preferably, is flared at its forward end 28a into the forwardportion of the blade 12. A removable downwardly extending transversecenterboard M can be inserted in a corresponding well 32 in the snowshoeblade 12. The centerboard 30, preferably, is stepped at 34 to provide afriction-fit within the centerboard well 32. It will be appreciated thatthe centerboard 30 can be used as an alternative to or in conjunctionwith the anti-backslip skeg 28. The use of both devices for inhibitingrearward slipping movement of the snowshoe is desirable when snowshoeswill be used for climbing relatively steep slopes in unpacked snow.Given the downwardly concave configuration of the lower snow-engagingsurface portion 20, it will be appreciated that the loose snow will becompacted within the area and immediately beneath the arch formed by thelower surface portion 20. The compaction and entrapment of the snowdensities the snow to provide a better bite for the anti-backslip skeg28 and/or anti'backslip centerboard 30.

The structural rigidity of the snowshoe blade 12 can be increased, ifdesired, by means of a longitudinally extending keel 36. In thepreferred embodiment, the keel 36 is integrally molded with the snowshoeblade 12. In addition to providing increased structural rigidity, thekeel also helps to minimize ankle roll" for the wearer.

Representative dimensions for the improved snowshoe 10 are as follows:length 42 to 50 inches, width 7 5% inches, skeg 28 located approximately1 foot from the trailing edge 36 of the blade 12, and the head of theboot binding 18 located approximately 26 inches from the trailing edge36 of the blade. The radius of the downwardly concave snow-engaginglower surface portion is approximately 6 to 8 inches. However, it shouldbe noted that the radius does not have to be constant and in thepreferred embodiment, the forward portion of the blade 12 in front ofskeg 28 has a flatter radius, e.g., 8 inches, than the portion of theblade behind the skeg 28 which has a radius of approximately 6 inches.

Having described in detail a preferred embodiment of my invention, itwill be apparent that a number of modifications can be made thereinwithout departing from the scope of the appended claims. For example,although only one skeg 28 has been shown in the drawings, it will beappreciated that a plurality of skegs can be formed within thedownwardly concave snowengaging lower surface portion 20.

What I claim and desire to protect by Letters Patent of the UnitedStates is:

1. A snowshoe comprising:

1. a longitudinal blade having an upwardly extending leading edge, ahorizontal portion on the upper surface of the blade for mounting a bootbinding, and, in transverse cross-section, forward and rearwarddownwardly concave snow engaging lower surface portions; and,

2. means for inhibiting rearward slipping movement of the snowshoe whileallowing forward gliding movement thereof, said means being locatedbetween said forward and rearward downwardly concave lower surfaceportions.

2. The snowshoe of claim 1 wherein said rearward slipping movementinhibiting means comprises at least one transverse, downwardly extendingskeg.

3. The snowshoe of claim 2 further characterized by a plurality oftransverse downwardly extending skegs.

4. The snowshoe of claim 3 wherein said skeg extends downwardly acrossthe entire width of the rearward downwardly concave lower surfaceportion.

5. The snowshoe of claim 3 wherein said skeg is flared forwardly andupwardly within said forward concave lower surface portion to provide asmooth transitional surface therein.

6. The snowshoe of claim l further characterized by said blade having atleast one longitudinal, downwardly extending keel located within theconcave lower surface portions of said blade.

7. The snowshoe of claim 1 wherein said forward and rearward concavedownwardly lower surface portions have different radii.

8. The showshoe of claim 7 wherein said forward concave lower surfaceportion has a longer radius than said rearward concave lower surfaceportion. 9. The snowshoe of claim 1 wherein said rearward slippingmovement inibiting means comprises a removable centerboard meansextending downwardly beyond and transversely with respect to the concavedownwardly lower surface portions of said snowshoe blade for inhibitingrearward slipping movement.

10. The snowshoe of claim 1 wherein said blade has, in transversecross-section, an upwardly convex upper surface portion.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTIONPATENT NO. I 3 755 92 DATED September 4, 1973 lN\/ ENTOR(S) HenryAlexander Dearborn It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Col.l, line 10, "Conventinnal" should be Conventional--;

Col. 1, line 11, "flotation" should be -floatation-;

Col. 1, line 46, the number 21 should be deleted;

Col. 2, line 30, after "blade" insert --l2- and delete the word"inhibiting";

Col. 2, line 33, after "provided" delete the word "rearward" and insert-in-;

C01. 2, line 42, after "corresponding" insert --"centerboard"- Signedand Sealed this tenth D3) of February 1976 [SEAL] A ttes t:

RUTH C. MA SON C. MARSHALL DANN A lesli g Offizer Commissioner ofPatentsand Trademarks

1. A snowshoe comprising:
 1. a longitudinal blade having an upwardlyextending leading edge, a horizontal portion on the upper surface of theblade for mounting a boot binding, and, in transverse cross-section,forward and rearward downwardly concave snow engaging lower surfaceportions; and,
 2. means for inhibiting rearward slipping movement of thesnowshoe while allowing forward gliding movement thereof, said meansbeing located between said forward and rearward downwardly concave lowersurface portions.
 2. means for inhibiting rearward slipping movement ofthe snowshoe while allowing forward gliding movement thereof, said meansbeing located between said forward and rearward downwardly concave lowersurface portions.
 2. The snowshoe of claim 1 wherein said rearwardslipping movement inhibiting means comprises at least one transverse,downwardly extending skeg.
 3. The snowshoe of claim 2 furthercharacterized by a plurality of transverse downwardly extending skegs.4. The snowshoe of claim 3 wherein said skeg extends downwardly acrossthe entire width of the rearward downwardly concave lower surfaceportion.
 5. The snowshoe of claim 3 wherein said skeg is flaredforwardly and upwardly within said forward concave lower surface portionto provide a smooth transitional surface therein.
 6. The snowshoe ofclaim 1 further characterized by said blade having at least onelongitudinal, downwardly extending keel located within the concave lowersurface portions of said blade.
 7. The snowshoe of claim 1 wherein saidforward and rearward concave downwardly lower surface portions havedifferent radii.
 8. The showshoe of claim 7 wherein said forward concavelower surface portion has a longer radius than said rearward concavelower surface portion.
 9. The snowshoe of claim 1 wherein said rearwardslipping movement inibiting means comprises a removable centerboardmeans extending downwardly beyond and transversely with respect to theconcave downwardly lower surface portions of said snowshoe blade forinhibiting rearward slipping movement.
 10. The snowshoe of claim 1wherein said blade has, in transverse cross-section, an upwardly convexupper surface portion.